Driving mechanism to maintain constant the required length of an endless driving means



Patented Nov.v 16,(

Vrf*UNI'IEQSTATES t l; ,f 2,099,.I218` y f DRIVING."lsECiIANIsM To MAINTAIN'coN-'p f STANT THE REQUIRED LENGTH F AN ENDLESS DRIVING MEANS `FredericltA Nicholson andY Wilmot T.)Pi'itcha'rd`,

Y* Seattle,- Wash., assignors to Stetson-Ross Mal chineCompany,A `Seattle, Wash., a corporation v y 1-'App1icati6 December 21,1936, serial No. `116,460

e `Thisinvention relates to a driving mechanism` and particularly to means to maintain substanf Xftially constant the required lengthof an endless driving means'tobe threaded overazplurality of V5 Wheels; Some 0f yWhich are mounted on movable wsupportg.

l This `application isrelated to our co-pending i `applications Serial Nos. 116,961,f 116',962,v 116,963,

- i In the priorartjwhere an endless driving means l `was threaded overfa pluralltyofvwheels, some of 5 which wheels were mounted on movable supports,

y y. it has been the practice to use tightener means to `maintain the .propertension on the endless driving means. Such kdevices operated satisfactorily where thetightener was placed on the slack .sideof the endless driving means.; However', such t prior art devices.` which `generally included a spring loadedgor.gravityweighted tightener, did

notoperate satisfactorilywhere the direction of `travel of the driving means `was subject fto; re-

2.5versal. .This for rthejsimple reason, that upon reversal, the tightener was nolonger` on the slack side of the driving means.l `Where reversiblepend- "less driving means were .employed over aplurality .otwheelaA some 'of whichjwere mounted onmoval .3 0 able supports,l the priorjart has gonetov complex mechanisms inyany attempt to :maintain thede- `Qsiredtensionof the endless driving means.l Such l t prior art devices were .not-satisfactory as they didunot provide the desired degree: of simplicityI s 35 to preventeostly shut-downs andgcontinual ret pairof the mechanism. Also where heavy driving t strains were encountered, the difficulties were in,

` yIt is the object vof ourpinventionto provide a 40 `fslmple, etlicient and l practical *mechanism` which will :permitganendlessdriving 7means lto be threaded over a plurality of wheels, someof which L `are mounted on movable supports, and'where the length of the endless driving means will remain .fisubstantially constant despite theV movement of f some of the wheel means.

a pivotal t supporting means with t tion to provide wheel means` mounted on opposite sides ofthe 'i pivotal lmounting ina `mechanism employing a plurality of wheels andan endlessl driving means, whereby pivotal `movement oithe rpivotalxsup- `portingfmeanswill move one,wheellsupported l v Feeding-mechanism indicated" generally lby Il is kshown at the infeedingv' end of the machine.

thereon in a direction tending to tighten the end` 55 less driving means and"`move the other wheel sup- It ismore partic larlyan objecty of this invenported thereon in a direction"y tending to loosenA t' .the endless driving means. Thelength of endless driving means required willtherefore remain, for practical purposes, substantially constant despite :the fact thatsome of the wheels in the mechanism are mounted on movable supports.

The above mentioned general objects of our invention, together with` others inherent in the same,l are attained by thevmechanism, illustrated in the following drawing,ythe same being preferred exemplary forms of embodiment of our invention, throughout which drawing like'reference numerals indicate like parts: l v i .v Figure l is a view in elevation, with parts' removed, of a planer mechanism embodying this invention; i f

v r Figure 2 is aodetached fragmentary view in elevation, of. the particularA portion of the driving mechanism embodied in thisinvention,` showing -by dot and dash lines a'position which thepivotal support and wheels thereon may assume; I f Figure 3, is a. detached view partly in rsection vand ypartly in 4elevation of adjusting means for moving an upper feed roll of theplaner mechanism and the pivotally mounted wheel support which is connected therewith;y

Figurev 4 is a detached sectional view taken on vsubstantially line 4--4 of Figure 3; and

Figure is a view of a modiiiedform of this inf vention, which gure-islsimilar to Figure k2,ibut

support another wheel..

Y showingin addition theretov means to adjustably y In describing and illustratingithis invention we tion is not limited toany such specific application and the same is set forth only as illustrative of connection the mechanism may obviously bei-used in connection with any `wheel means and endless driving means, threaded thereover and sprockets and an endless sprocket chain are only ,examples thereof. i f

anism are not shown and willi'be only generally described, as such details"V arectmsiderc-:d` essen'- tial to this invention. y .i-

A frame I0 supports the planer mechanism.

Yhave shown the same as applicable in connection l with the driving of feed rolls ofa pianingdevice. n

AIt is to be expressly understood that-this inven- 1 :sav

Thisfeeding mechanism urges lumber stock past la lower cutter head mechanism I2 and an upper cutter head mechanism I3. The lumber 'is then urged past edge matcher mechanism indicated generally by I4. Lower and upper face pattern forming cutter head mechanisms I5 and I6 may be provided in connection with the planerfmechamsm.

The outfeeding mechanism, with which this invention is concerned, is shown at the right of Figure 1 of the drawing. Here an upper feed roll I1, see Figs. 3 and 4, is journaled in a yoke member I8 on a shaft I9. This yoke member I8 is flxedly secured to a shaft 20, as by key means 2I. A sprocket wheel 22 is mounted on shaft lI9 and the sprocket wheel 23 is mounted on the adjustable mechanism indicated generally by the arrowr 24 in Fig. 4. 'Ihus the shaft 20 serves as a fulcrum with sprocket 22 mounted on one side thereof and sprocket 23 on the other side thereof. As the sprocket 22 is raised, sprocket 23 is lowered and vice versa.

This means, for raising the feed rl I1 and in turn lfor pivoting the sprockets 22 and 23 about the shaft 20, is shown in Figs. 3 and 4 of the drawing. One end ofthe link member 25 is pivotally secured to the yoke member I8 and the other end ofthe link member 25 is pivotally secured to another link member .26. The link member 26 is slldable within a threaded sleeve 21, which sleeve is meshed with an internally threaded Worm Wheel 28. 'I'he worm wheel 28 'is held inplace by the portions of the frame I0. A compression spring 29 is positioned on link 26 and between nut means 30 and the threaded sleeve 21. member 2 6 Awill moveupwardly in response to upward movement of the feed roll I1 independently of the threaded sleeve 21.' l Also when the threadedsleeve 21 is moved `upwardly by rotation of worm wheel 28, the rolls I1 will be moved" upwardly and the sameV springtension will be provided, resiliently resistingupward movement of the feed rolls I1 independentlyof` the threaded 1 Movement of the worm wheel 28 mayy be had bythe operation of the worm-3| and` sleeve 21.

hand wheel32. y

Thus, lumber passing' between feed roll I1 andlfeed roll 3I,`if the same is thicker than the= sizeof the opening between said. feed rolls, will-` raise rfeed roll I1 by compressing spring 29. Also Y thelowerposition of the feed roll I1 is determined `vwhen stop 32 rests against threaded sleeve 21.

As thefeedroll I1 raises and lowers, carrying 1 shaft I9 therewith, the: sprocket wheel 22, which is connected with said shaft I9, likewise raises and lowers. At the same time the shaft 20 is angularly moved by .the raising and lowering of feed roll- I1, which in turn raises and vlowers sprocket wheel 23, .which is connected with the shaft 20, by reason of the adjusting mechanism generally indicated by 24 in Fig.`4. Thistadjustk ing mechanism 24 provides for relative movement between the sprocket wheel 23 and the sprocket wheel 22, and for initial adjustment of the tension4 of endless sprocket chai-n 33 which will be hereinafter discussed.

'This adjusting mechanism comprises an arm member 34 keyed to the shaft26. The arm member 34 is provided with a. pawl 35, shown best in Fig. 2. Another arm member 36 is pivotally secured on shaft 20 and has va U-shaped portion 31 operatively positioned as respects the said pawl 35. Set screws 38 provide for adjustable rela-4 tive movement between the U-shaped portion 31 and the pawl 35land in turnfadjustable relative Thus, the link f Vadjust the mechanism described and then the cap` screws 40 may be tightened to serve as additional means to hold such adjustment.

The adjustable mechanism 24 just described thus comprises a pivotal supporting means where a wheel, such as a sprocket wheel 22, is rotatably mounted thereon at one side of the pivotal support and another wheel, such as a sprocket wheel 23, is rotatably mounted thereon and to the other side of 'said pivotal support. As the sprocket wheel 22 rises because of lumber passing through the planing machine, the sprocket wheel 23 will be loweredand vice versa.

The lower-'feed'roll 3I is supported by shaft 4I and another driven wheel such as sprocket wheel 42 is supported on shaft 4I. A driving wheel, such 'as-sprocket wheely 43,fis connected byfendless driving means SintoV aisourceffof power 1(not shown) and such sprocket wheel 43. `is journaled in the main frame I- of the machine. Anendy less driving means, such as .the endlesschain 44,

is threaded around sprocket wheels 43,23, 22-and -42.y To provideyan `initial-adjustment for such endless chain and: to compensate for wear between such chain'and the said sprocket wheels., the adjusting mechanism gencrallyrindicated by 24 in Fien-'41s provided. After: the endless chain 44 is initially adjusted, any diierencein length of chain required because of upward or downward movement of the r`oll I 1 and vin turn'the sprocket wheel 22 is-substantially compensated for by -the downward -org upward movement '.fof'- the sprocket wheel-23. Referring to'Fig.' 2,"asz the sprocket wheel` 22 moves from the full line position to the dotarid dash line position, the -sprocket wheel-23valso movesvfrom its-full lineposition to 4its..dot anddashlinep'osition and-thus as one lap of the chain becomeslonger, the other-lap of the chain becomes shorter in substantially the same'proportions.A t :f 'i y .f This rprovidesv'for a Ifeeding mechanism'where in asprocketwheel mayraise Vor lower -without substantially changing fthe' length of vthe feeding 1chain rover.: laf-plurality"r of sprockets whichr include the `sprocket which is thus raising and low- .eringx This has proved a veryv practical `device and Where the movement of a "sprocket wheel is within the vlimits requiredv for .the outfeeding rolls of ay planingmachine,such:as upytofour `or ve inches.- the `clia'in 4maybe'-threadediover sprocket wheels without lothertiglite'nei'r means being employed. 'l vWheri.'fsprocket'f'wheels and chains are employed; the depth of contact between the teeth on the sprocket wheels andthe chainmay be initially selected so that small dis- -crepancies will not practically affect lthe operation. Also where belt vor" chain tighteners are eliminated, the direction of movement of the chainmay be reversed from time to Itime without inconvenience'or damage to the parts.

At the infeeding end ofV thef'planing device shown in Figure 1, we have shown a drivingmechanism, generally` indicated 'by II whichv is the subject matterof our said copending' applications, Serial Nos. 116,961, and 116,962.v This driving mechanism provides for the use of feed beds or two upper and lowerfeed rolls. In Fig. of the drawing, we have shown the present inven- Vtionin connection with the` infeeding end of a machine where anupper and a lower feed roll Sprocket mounted adjustablemechanism generally indicated by 41. f'I'his mechanism may be similar to l "the adjustablefmechanism described in connection with Figs. Zand 4 and Iwhich wasl indicated f "generally `by 24 in Fig.` 4. A shaft 48 is mounted 2,099,218 i are employed. vHere an upper feedy roll (not Obviously the invention *.herein can be'` readily` shown) is 'mounted on a shaft 45.'l

wheel 46 yis mounted on said shaft 45. The wheel 46 is mounted on the pivotally on the adjustable rnechanis`rn'-414 and rotatably supports sprocketwheel 49 to one side of the shaft 50, which shaftr 50'serves as a pivotal sup,-v

port. A drivenfsprocket wheel52, which correret wheel 52 is connectedby ani'endles's drivlngv sponds with the driven sprocketwheel 43y of Figs. l and 2, is illustrated` Thisdriving sprockof power "(not shown). Thus las" the upperfeed roll (not shownl" moves upwardly'and carriesr with it the sprocket wheel 46 the sprocket Wheel 49 will be lowered, providing compensation as# discussed in f-connection withf' Figs. l1 and 2..

In Fig. 5 the lower feed roll (not shownlqis mounted on a shaft 53. Orr this shaft 53 a driven l sprocket wheel 54 is mounted. `An arm 55 has one end rotatably mounting the shaft 53 and the other end of the arm 55 is pivotally supported by a shaft 56connected to the main frame I0 of the machine. A link 51 has one end pivotally secured to the arm 55 and the other end slidably extending through one arm of a bell crank 59. Compression spring means 58 is provided on link 51 between bell crank 59 and a fixed collar 61 on said link 51. Nut means 68 is provided on link 51 below bell crank 59. A link 50 has one end connected with the other arm ofthe bell crank 59 and Vthe other end of link 60 is connected with a screw 6I. The screw 6l is threadedlyv engaged with a worm Wheel 62, which worm wheel 62 is secured inplace by portions of the main frame of the machine 63. A worm 64 is connected with the worm wheel 62 and angular movement of the worm'64 will impart a rotary movement` to the worm wheel 62,*causin'g the screw 6I and link 60 to 'move toward and away from` the `worm wheel 62. This movementv through the bell crank and link means shown will raise or lower the link 51 and in turn the arm 55 and the feed roll supported on the shaft 53. Also I as different sized pieces of' lumber are generally encountered at the infeeding end of the machine, the feed` roll supported on the rshaft 53 may move up` and down as indicated by the full line and theA dot and dashv line positions, -which will compress Athe spring 56, permitting such movement.' As the lower feed roll 3| and the sprocket wheel54 move up and down independ- Jently of the upper feedroll I1 and the sprocket wheel 46 connectedtherewith, this will not'suby stantially change the length of endless chain required, as isset forth and explained in our copending application Serial No. 116,962. An endless driving means, such as an endless chain r65, is

threaded around the sprocket wheels 49, 46, 54 andr 52. The sprocket wheel 52 is mounted on the main Af rame of the machine and is connected to asource of power (not shown) by means of f endless driving means 5I, as previously described.

In the foregoing we have described the invention as applicable toa planing device,l such as that disclosed in our copending application Serial No. 91,568. Insuch a planing device the lower bed is resilientlymounted as distinguished vfrom the commercial prior art planing machines where the upper beds are resilientlyf mounted.

A sprocket p lication Serial No. 91,568. Obviously,` changes may be made adapted to ordinary planing machines as' well as to the Aplaning mechanism disclosed in saidapin the forms, dimensions and arrangement of the parts of our forms of embodiment.

We claim:

y of theclass described, `wheel said 1 wheel mountingA means',

said pivotal supporting .means;,. other wheel f f mountingmeans; a third. rotatable pwheelv mountedon saidother wheelmountingmeans and offset lfrelative'to'said first and second wheels; V.and an Y n endlesswdrivingA means `threadedfloversaid. first, A,

invention, without ydeparting from. the principle, thereof,.the above setting'` forth onlyrpreferred second and third'wheels, whereby, upon pivotalv movement of said pivotal supporting means the` f difference in length of the endless driving means required between the third wheel and the first wheel is substantially compensated for by the length of the endless driving means required between the third wheel and the second wheel.

2. In a device of the class described, wheel mounting means; pivotal vsupporting means for Y,

said wheel mounting means; a rst 'rotatable wheel mounted on said wheel mounting means and to one side ofthe said pivotal supporting means; a second rotatable wheel mounted on said wheel mounting means'and to the other side i of said'pivotal supporting means; means opera-k y. tively yconnecting with'A said wheel mounting 'means and providing for relativemovement between said rst and Asecond wheels; other wheel mounting means; a third rotatable wheel mounted on said other wheel mounting means and offset relative toksaid first and second wheels; andan endless driving means threaded over said first, second and third wheels, whereby, upon pivotal movement ofA said pivotal supporting means the difference 4in length of the endless driving meansl requiredbetween the third wheel andthe first wheel is substantially compensated for bythe length of the endless driving means required betweenthe third wheel and the second wheel.

3. In a device of the cla-ss described,` a mounting means; pivotal supporting means for said i" mounting means; a feed roll journaled in said mounting means and to one side of said pivotal vsupporting means; a first driven rotatable ,wheel mounted on said feed roll; a second driven rotatable wheel mounted on said mountingmeans and to the other side of said pivotal supporting means; other wheelr mounting means; a` third rotatable 4driving wheelr mounted on said other wheel mounting means and offset relatively to said first and second wheels; and an endless driving means threaded over saidrfirst, second and third wheels, whereby, upon pivotalV move-` ment of said feed roll and said pivotal supporting means the difference in length of the endless driving means required between the thirdwheel and the first wheel is substantially compensated for by the length of the endless drivingmeans 'lol required between the third wheel and the second wheel. s

4. In a device ofthe class described. a mount,- ing means; pivotal supporting meansofor said i mounting means; a, feed roll journaled in said mounting means and to one side of said pivotal supporting means; a flrst driven wheel mounted on said feed roll; a second driven rotatable wheel mounted on said wheel mounting means and' to the otherv side of the pivotal support; other wheel mounting means; a third driving rotatable wheel mountedon said othervwheel mounting means and offset relatively to said first and second wheel; another feed roll; a fourth driven wheel mounted on said other feed roll; and an endless chain driving means threaded over said rst, second, third, and fourth wheels, whereby, upon pivotal movement of said feed-roll and said pivotal supporting means the length of the endless drivingmeans required to thread between said first, second, third and fourth wheels will remain substantially constant.

5. In a device of the class described, a mounting means; pivotal supporting means for 4said mounting means; a feed roll journaled in said mounting means and to one side of said pivotal supporting means; a rst driven wheel mounted on said feed roll; a second driven rotatable wheel mounted on'said wheel mounting meansand to the otherside of the pivotal support; other wheel mounting means; a third driving rotatable wheel vmounted on said other wheel mounting means FREDERICK A. NICHOLSON. WILMo'r T. PRITCHARD. 

